A typical motion-control system, e.g., an electromechanical control system, includes a mechanical subsystem and a control subsystem. The mechanical subsystem includes electromechanical components that can be represented as masses, springs, dampers, and actuators. The actuators can be electric motors, hydraulic actuators, piezoelectric actuators, etc. The control subsystem includes a control module evaluating control methods, electronics, for instance, amplifiers, sensors, etc. The actuators are controlled by the control modules responding to tasks from user and other inputs and signals from sensors. The actuators controlled by the control modules are herein referred to as controllable actuators.
FIG. 1 shows a schematic of conventional single-axis motion-control system. The subsystem of the system of FIG. 1A includes a base mass 151 and a load mass 152, a base spring 153, a base damper 154 and a load damper 155, and a controllable actuator 156, which usually is an electric motor. The electric motor is connected to the base and the load mass. The rotation or linear movement of the electric motor can exert a force on the load mass and the base mass, thus moving the load mass in a specific direction, e.g., the horizontal x direction. One purpose of the single-axis motion-control system is to move the load mass to a specific position along the x direction. The mechanical subsystem is designed according to some specifications e.g. typical tasks of the system, a size of the system, and cost.
One disadvantage of that motion-control system is a lack of flexibility and unsatisfactory performance. This is due to the fixed and decoupled design of the mechanical subsystem and the control subsystem. During the operation of such a system, it is difficult or even impossible to change at least some of those parameters, i.e., the system has a fixed electromechanical design. Accordingly, conventional methods for optimizing the operation of the motion-control system focus on control methods running in the control module to command controllable actuators.
However, there is a need to optimize the operation of the motion-control system by redesigning the mechanical subsystem and the control subsystem online for different tasks or criteria.